The Banner NWS TUS balloon sounding launched at around 3:30 PM from the Banner University of Arizona. The temperature of the Cirrocumulus was indicated to be about -36° C, at about 26,000 feet above Catalina (29,000 feet ASL) and yet portions of the Cc had liquid droplets. The higher vellums of Cirrostratus or Cirrus were located.

Photos of yesterday’s patterns

I could literally hear the cameras clicking all over Catalina and Oro Valley as these patterns showed up, moving in from the southwest as the increasing numbers of cloud-centric folk lost control of themselves. Reflecting that general loss of control, which affected yours truly, too many photos will be posted here. Below holey clouds with icy centers, but not ones caused by aircraft:

And look closely at the fine patterns, lines and granulations in these shots! Truly mesmerizing.

But what’s missing in this photo above? There was no iridescence seen around the sun where we normally look for it suggesting that those Cirrocumulus clouds nearest the sun were composed of ice crystals, and not tiny droplets. Iridescence is rarely seen next to the sun due to ice crystals because they are usually the result of the freezing of existing droplets, that then grow rapidly as ice particles to sizes too large to produce diffraction phenomenon close to the sun. Where’s my Lear jet, so’s I can confirm these speculations?!! I would very much like to have one on “stand by”, in case I think of something. Below, a wonderful example of no iridescence even though newly formed clouds are by the sun:

4:21 PM. An outstanding example of no iridescence, maybe one of the best ever taken! The power pole shows signs of being in an archaic neighborhood.

A jet runs through it

Or so I thought. In this chapter of cloud-maven.com, we inspect the photos of a commercial jet flying at or near the level of these clouds and determine what happened. I was quite excited to see this happen because we would now determine whether there were any liquid droplets in what to the eye of the amateur cloud watching person would be a liquid droplet Altocumulus clouds. Here the size of the elements are just a bit too large to lump it into the Cirrocumulus category, if you care. So, with heart pounding, took this sequence of photos:

4:23 PM. A commercial jet streams into it seems, the Altocumulus layer. Or did it? CMP thought so.

Let is go zooming:

4:23 PM. Looks to have descended to below this layer. Note sun glint on aircraft.4:23 PM. Zoomin’ some more.4:26 PM. But, as the location of the aircraft path slipped downwind rapidly, there was NOTHING! I could not believe it! No ice canal with a clearing around it, and no contrail inside these clouds. The clearing would have occurred had the aircraft penetrated supercooled droplets leaving an ice canal. But, if the cloud was all ice, a penetration by an aircraft should have left a contrail, as they do in cirriform clouds. The conclusion? As close to this layer as the aircraft was, it did NOT apparently go into it. Amazing to this eye.4:25 PM. Looking downwind at those “Altocumulo-cirrus” clouds, all ice from almost the very leading, upwind edge due to that -36°C temperature they were at. Though overhead, as you saw in the photos below, they might be reckoned as plain Altocumulus, and not solely composed of ice ones.

By the way, if you caught it, there were a couple of standard, aircraft-produced, “hole punch” clouds at the very upwind, formative portion of this patch of clouds before it got here. These photos pretty much prove that the Cc at the formative end at that time was composed of highly supercooled droplets and that the passage of an aircraft produced ice, that caused a fall out hole.

1:52 PM. Hole punches caused by aircraft in the Cirrocumulus to Cirrus patch that moved over us later. Clouds like these do not move at the speed of the wind, about 60mph up there yesterday at this level, but rather, the air moves through it a hump in the airflow that moves much more slowly than the wind. Note the slight iridescence in the hole on the right.